Many telephony systems include advanced features that enhance user capabilities. For instance, “call waiting” is a well-known feature of telephony systems that notifies a caller when another call is coming in during an active call. “Caller ID” is another well-known feature that displays the originating telephone number and the subscriber's name associated with that number to the called party before the called party answers a telephone call. Still another configurable feature is “call forwarding”, wherein incoming calls to a particular directory number are automatically routed to another number. A number of variations to the basic call forwarding feature also exist. By way of example, “call forward busy” is a feature that re-routes incoming calls to an alternate line only when the first line is in use. Similarly, “call forward no answer” is a configurable feature that re-routes incoming calls from one phone to another phone when the first phone is not answered after a certain number of rings.
A number of commercial communication system products are available that combine call processing and Internet Protocol (IP) telephony with many of the functions of a conventional IP-private branch exchange (PBX) system for business enterprises. For instance, Cisco's CallManager™ is a software-based call processing component that extends enterprise telephony features and functions to packet telephony network devices such as IP phones, media processing devices, voice-over-IP (VoIP) gateways, and multimedia applications. Additional data, voice, and video services such as unified messaging, multimedia conferencing, collaborative contact centers, and interactive multimedia response systems may interact with the IP telephony solution through the CallManager™ open telephony application programming interface (API). In a version of the CallManager™ call processing software, users may set various preferences on their telephone device, such as incoming call ring tones for different caller IDs and/or call priority (e.g., siren for important calls, chirp for medium priority calls, etc.), call display settings for displaying pictures or photos of a caller, etc. However, when a user forwards their calls to another telephone device these preference settings are not applied at the forwarded destination telephone device.